SARAJEVO, Bosnia-Herzegovina -- Al-Qaida terrorists planned a devastating attack on Americans in Sarajevo after meeting in Bulgaria to identify European targets, a high-ranking Bosnian official said Saturday.

The official, who spoke on condition of anonymity, told The Associated Press that intelligence reports on the meeting in Sofia, the Bulgarian capital, prompted a special government session Thursday night to discuss threats against the U.S. Embassy and embassies of European countries.

At the Sofia meeting, members of al-Qaida decided that "in Sarajevo something will happen to Americans similar to New York last September," said the official. He did not say when the al-Qaida meeting was held or who attended.

The U.S. Embassy in Bosnia shut down to the public on Wednesday after receiving word of a possible terrorist threat. The embassy closed entirely on Friday, and the next day Bosnian special police forces were seen around the compound along with normal U.S. security units.

In Washington, State Department spokeswoman Jo-Anne Prokopowicz said the embassy will remain closed over the weekend and that security measures would be reviewed before deciding whether to reopen Monday.

Officials at the Pentagon said they had no information about a specific al-Qaida threat in Bosnia.

Bulgaria's Foreign Ministry said it had received no information on such a meeting in Sofia, either "from Bosnian authorities or from any other official sources." It promised an investigation if "this information proves to be serious" and ordered the embassy in Sarajevo to look into the situation.

A senior Bulgarian Interior Ministry official, Boiko Borisov, and national police chief Vasil Vasilev both said in televised comments that that they knew nothing about any Bulgarian connection in the alleged Sarajevo plot. "I don't know what this information is about," Vasilev said.

On Tuesday, just a day before the U.S. Embassy received the threats, Bosnian police raided an Islamic charity, Bosnian Ideal Future, also known as Benevolentia International Foundation, seizing weapons, plans for making bombs, booby-traps and bogus passports.

On Friday, police announced they had arrested Munib Zahiragic, a Bosnian citizen and the head of the Bosnian chapter of the charity. Zahiragic is also a former member of the Bosnian Muslim secret police, AID.

Zahiragic was arrested on charges of espionage, which carries a maximum 10 years in prison. No details on whom he was supposed to be spying for were released.

As a part of the war on terrorism, Bosnia's government in January ordered an investigation into the work of foreign humanitarian agencies. Two weeks ago, investigators reported funds were missing from three Islamic charities, among them Benevolentia.

The United States recently froze the assets of Benevolentia, with head offices in Illinois and New Jersey.

The U.S. and British embassies were closed for several days in October because of terrorist threats. They reopened after local police arrested six naturalized Bosnians, all of them Algerian natives, suspected of plotting post-Sept. 11 attacks on U.S. interests in Bosnia and elsewhere.

The suspects were handed over to U.S. authorities in January, and now are being held at the U.S. military base in Guantanamo Bay, Cuba. Five of the six were employed as humanitarian aid workers; one was suspected of being Osama bin Laden's top lieutenant for Europe.